Universal Tool Holders for right or left hand turning, facing, chamfering and boring:#20 and #30 Universal Tool Holder: Provide for many angular turning, contouring and chamfering operations. The cartridge has 12 indexing positions at 15 degree intervals.#22 Universal Turning & Boring Holder: Its two dovetail design leads to a wide range of applications by permitting front and rear turning, contouring, boring and facing operations.All holders assure proper cutting edge and clearance angles at all indexing points.Cartridges can be easily adapted on bars and other special tools to meet any specifications. Cartridges can be supplied separately or combined with a cartridge cradle.Cartridge CRT-20 and CRT-30 are interchangeable.